National Dental Assisting Examining Board (NDAEB) Practice Exam

The height of contour on a tooth refers to what feature?

1. The bulge or widest point on a specific surface of the crown

2. The cutting edge of a tooth

3. The tip of the cusp

4. The root length of the tooth

The correct answer is: The bulge or widest point on a specific surface of the crown

The height of contour on a tooth specifically refers to the bulge or widest point on a particular surface of the crown. This feature is significant as it plays an essential role in the proper function and aesthetics of teeth, influencing how they interdigitate during occlusion (the contact between upper and lower teeth). The height of contour contributes to proper food passage during chewing and helps maintain the health of surrounding gum tissues by promoting proper flow of saliva and preventing plaque accumulation. Other options like the cutting edge of a tooth, the tip of the cusp, and the root length of the tooth are related to different aspects of tooth anatomy. The cutting edge pertains to the sharp edge where incisal teeth meet for shearing food, while the tip of the cusp is a specific point on the crown of a molar or premolar meant for grinding, and the root length refers to the part of the tooth embedded in the bone. While these components are important in understanding tooth morphology and function, they do not define the height of contour.